Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak)

[HburgEagle]

I've been deferring fixing the valley leak in my LX for awhile now for various reasons. But I think it's finally time to get it done. It's been awhile since I've read through the various threads on this. I could use some inputs on what I think I've gleaned from them re: what to do - please help with any corrections or updates that I may have missed. I'm not capable so I'm going to have a shop do the work; I just want to make sure I'm explicit with some key points.

1. Have the shop use gasket compound 1282b (08826-00100), black rubbery compound vs what may be the factory default grey compound.
2. Replace the manifold gasket as well (17171-0S030); don't reuse the existing gaskets
3. Replace the PCV valve (12204-38010), union pipe o-rings (96761-35035), and PCV separator gasket (12273-38020)
4. Clean 3 radiators (A/T oil cooler, AC condenser, Engine) fins.
5. Replace the thermostat, serpentine belt and radiator cap. I've got 120K miles. 2nd owner and not sure if the thermostat has been replaced before. Actually, I've had the water pump and belt replaced I think (several years ago). Perhaps the thermostat was replaced at that time as well.
6. I'm not really clear on this one -- replace SAI SW BK1 and BK2 (not sure what these parts are). SAI pumps (including the internal filter)? Is this really necessary; I got the impression that it's expensive and may not be necessary (perhaps just recommended if appropriate?)

Anything listed that is incorrect, not necessary or not advised? Anything missing? Thanks!

I used the black FIPG and it seems to have worked fine. I was very careful to make sure I cleaned both mating surfaces very well and made sure everything was clean and dry before applying as evenly and thorough as possible. I also made a bunch of trial runs at setting it in place dry to make sure I had a clear path and to practice setting it in place to try and insure my sealant didn't get disturbed. I can't speak yet to it lasting long term so we'll see.

I did replace the manifold gaskets. They were cheap and it just made sense to me.

I followed the procedure from Timmy the Toolman to remove the SAIS valves. Much easier to unbolt it through the wheel well. But, be careful to retain the gaskets between the flanges.

 

[Dan Lee]

Thank you.

Okay so the instruction list stand at:
1. Have the shop use gasket compound 1282b (08826-00100), black rubbery compound vs what may be the factory default grey compound.
2. Replace the manifold gasket as well (17171-0S030); don't reuse the existing gaskets
3. Replace the PCV valve (12204-38010), union pipe o-rings (96761-35035), and PCV separator gasket (12273-38020)
4. Clean 3 radiators (A/T oil cooler, AC condenser, Engine) fins.
5. Replace the SAIS valve assembly; don't touch the pump assembly. ($500-700 adder?)
6. The water pump was replaced a few years ago. I'll assume that the serpentine belt and the thermostat were replace as well. Unless this is not typical?

 

[Ratchey]

Thank you.

Okay so the instruction list stand at:
1. Have the shop use gasket compound 1282b (08826-00100), black rubbery compound vs what may be the factory default grey compound.
2. Replace the manifold gasket as well (17171-0S030); don't reuse the existing gaskets
3. Replace the PCV valve (12204-38010), union pipe o-rings (96761-35035), and PCV separator gasket (12273-38020)
4. Clean 3 radiators (A/T oil cooler, AC condenser, Engine) fins.
5. Replace the SAIS valve assembly; don't touch the pump assembly. ($500-700 adder?)
6. The water pump was replaced a few years ago. I'll assume that the serpentine belt and the thermostat were replace as well. Unless this is not typical?

Depending on year and style, if cracked you might as well just replace the radiator.

 

[Dan Lee]

I'll take a look again. I can't tell if the radiator has been replaced before or not (I'm not the original owner). But it's still the old version. I don't think it's cracking at the moment - hard for my novice eyes to really tell. If the radiator has been replaced, maybe I'll keep it. If not, then maybe it's good to proactively replace while all the guts are out.

 

[HburgEagle]

Thank you.

Okay so the instruction list stand at:
1. Have the shop use gasket compound 1282b (08826-00100), black rubbery compound vs what may be the factory default grey compound.
2. Replace the manifold gasket as well (17171-0S030); don't reuse the existing gaskets
3. Replace the PCV valve (12204-38010), union pipe o-rings (96761-35035), and PCV separator gasket (12273-38020)
4. Clean 3 radiators (A/T oil cooler, AC condenser, Engine) fins.
5. Replace the SAIS valve assembly; don't touch the pump assembly. ($500-700 adder?)
6. The water pump was replaced a few years ago. I'll assume that the serpentine belt and the thermostat were replace as well. Unless this is not typical?

You don’t need to replace the SAIS valves. They are just in the way and you have to remove them to get the valley plate out. Just remove the valve assembly and set to the side. The gaskets between the two flanges you have to unbolt to remove it are metal and can be reused. Just make sure and retain them.

 

[Dan Lee]

Thanks, good to know. I had the impression that the SAIS valves needed to be replaced eventually (not sure what the general failure point is - 150K miles? I'd imagine it depends on the shape of the SAIS filter at the pump and the local environment). I've got about 130K miles so if that's the case, perhaps this would be a good time to replace.

I generally use the truck only for long distance trips so would hate for the SAIS to fail in that event. Is the SAIS failure somewhat predictable? (like tires or oil filters have an expected life)? Or is it more luck of the draw - could fail anytime or perhaps even never (300K miles and beyond)? I'm under the impression that it's on the more predictable side but I'm a novice. I've never heard of SAIS until this thread, never had a car where SAIS has failed. I'm not even sure if my car has an SAIS (sounds like it should).

I think the SAIS valve assembly is about $600 (assume labor not an issue since it needs to be removed to do fix the valley leak). I guess I'm unsure if I should pay the $600 now (predictable failure), or take the chance and do it later since it may never fail (however, if it does fail, it may cost $1600+ to fix if the shop needs to remove much of the same stuff as the valley leak fix).

 

[Acrad]

SAIS option for those that don’t know

Search By Vehicle: Product Results | Hewitt Technologies

Find compatible Secondary Air Injection Bypass Kits and Kit Addons for your Toyota or Lexus Truck and SUV.

hewitt-tech.com

 

[TeCKis300]

What did you guys find most effective to clean and prep the sealing surface for new FIPG? Went at it with a plastic razer which worked just okay.

 

[nwfl4runner]

What did you guys find most effective to clean and prep the sealing surface for new FIPG? Went at it with a plastic razer which worked just okay.

View attachment 3742149

I used wd-40 and a gray (ultra fine) scotch-brite

 

[sdnative]

I may have used a pinstripe eraser, but it's been a while and I don't remember exactly. Probably tried scotch-brite as well. Something that wouldn't scratch the sealing surface, although maybe micro scratches may help sealing?

 

[TeCKis300]

Thanks guys. After fumbling around my drawers, I found a new brass bristle brush. That and some carb cleaner seemed to do well enough. It's the surfaces where the leaks occurred that are the hardest to clean probably because of etching over time.

 

[bloc]

After fumbling around my drawers, I found a new brass bristle brush. That and some carb cleaner seemed to do well enough.

That's the best method I've found so far. Makes a little bit of a mess but effectively takes RTV off aluminum surfaces without damaging them.

 

[Cruisin911]

What did you guys find most effective to clean and prep the sealing surface for new FIPG? Went at it with a plastic razer which worked just okay.

View attachment 3742149

I used a drill with wire wheel. Made a mess but was relatively easy to vacuum up.

Of note, DO NOT use the cheaper FIPG from toyota. Use the $100/tube stuff. It's specifically made for this fix. It's a pain in the rear to do this repair. I had to pull it apart and do it twice due to an incorrect rubber O-ring on the transfer tube in the foreground of your picture. Make sure your diameters are correct and dont assume that the parts department gave you the right ones... mine was a hair too big and slipped out of position on the bottom where I couldn't see it until I refilled the system.

 

[TeCKis300]

I used a drill with wire wheel. Made a mess but was relatively easy to vacuum up.

Of note, DO NOT use the cheaper FIPG from toyota. Use the $100/tube stuff. It's specifically made for this fix. It's a pain in the rear to do this repair. I had to pull it apart and do it twice due to an incorrect rubber O-ring on the transfer tube in the foreground of your picture. Make sure your diameters are correct and dont assume that the parts department gave you the right ones... mine was a hair too big and slipped out of position on the bottom where I couldn't see it until I refilled the system.

Agreed. I just got done filling and bleeding tonight and everything was drum tight. Thanks to all the tips in this thread including watch areas that are easy to get wrong like the o-ring.

Totally agree with the $100 1282B FIPG. It's the price of a tank of gas after all, and that's definitely not worth all the labor to not do it right.

I'll say it was hard to glean all the great tips and stuff tucked in this thread. Might do another write-up...maybe. But it's all there.

For the next guy doing this job - if also flushing coolant. It's good to have 4 gallons on hand as mine took a total of 3.25 gal, which includes filling the overflow reservoir. Had to stop by the Yota dealer to grab that extra gallon today to finish the job.

 

[mfeferman]

Well, it was my turn to reseal the valley cover plate after months of disappearing coolant that eventually left a trail of pink crud all over the passenger side of the transmission bellhousing. 2008 LX with 178k miles. Never got a drop of coolant on the floor, but it was time to get it fixed. The big O-ring on the connecting tube to the block didn't seat properly the 1st time and it wasn't obvious until after I refilled the system and saw the small leak, so I had the pleasure of doing it all over again

The only thing I can add to everything that has already been mentioned is that putting those air injection valves back in is a major PITA job, especially if you don't have tiny hands. The 1st time I was able to eventually put everything back together as has been mentioned here (disconnect from the driver's side tube and tilt/push the valves back a little so the other screw can clear the passenger's side head). The 2nd time I gave up and looked for a better way. It turns out that there is nothing else holding that tube in place other than two 10mm nuts on the flange on the exhaust manifold, with very easy access thru the wheel well under the fender.

So, do yourself a favor next time and don't bother disconnecting the valves from the passenger side tube. Remove them together and don't mess with the little bolts that are nearly impossible to remove, and even more difficult to put back together.

Thanks for the recommendation to disconnect passenger side of SAIS piping from manifold instead of where the pipe attaches to the injection valves. It cut the time down a lot. However, I had to enlist my son's help to put it back in without the filter falling off. At the end of the day, it was still a PITA.

 

[muzzam]

Finally got everything done and put back together. It took me a good solid two days worth of work to complete this job(I definitely take my time), I am sure others here are more skilled at this hence the shorter time to complete the job. Few things that I would like to share:

1. First of all this thread and few other threads here were very helpful.
2. This Youtube video helped with disassembling up to the point of removing Secondary air injection pump. After that below post was very helpful in disassembling.
3. 
   
4. This post was very helpful in putting the gasket on
5. 
   
   
6. If you are new to this like me, then taking lots of pictures at every step is a big help.
7. The gasket glue that came off was much softer and brittle, kind of spoungy texture. Not sure if that was a different kind of gasket glue or it just deteriorated over time. I am not surprised it failed like it did. The new gasket glue dries to a much better rubber like texture. If it is the difference in glue then I think 1282b(08826-00100) should last much longer. I ended up using about 1/4th of the tube. Not sure what am I going to do with the rest. Perhaps donate to some mechanic.
8. I ended up replacing the manifold gasket(17171-0S030) as well since the original was kind of flattened.
9. Also replaced the PCV valve(12204-380100) and union pipe O-Rings(96761-35035). I used extremely tiny amount of brake parts safe grease to lubricate the O-Rings to slide in-place correctly. The total cost of parts was around 105$.
10. As suggested by others here practicing to put the heat exchanger plate back on helps a lot to develop a technique to put the plate back on without messing up the gasket glue:
11. 
    
    
12. After putting everything back together the Traction control(solid), check engine(solid) and 4Lo(blinking) lights came on. Someone on youtube suggested to disconnect battery terminals and short them to reset everything which resolved my issue.
13. Shout out to everyone else who has contributed so far to the information required in getting this job done.

I am sure you have done a great job as you explained.
I just found out that I have got same issue on my LX570 2011, and I am at the stage of ordering parts now.

So far I have listed these few.

Part Description	Part NO.
Manifold Gasket	17171-0S030
PCV valve	12204-380100
Water Inlet Engine Cover Pipe Gasket (O-Ring)	96761-35035
Seal Packing (Tube)	1282B

Should I add any other part to the list? Do I MUST need to change the VP Cover plate or I can used the old one if not damaged?
Also if you can suggest the sources to procure these as you mentioned it cost you way cheaper than what I am looking at online.

Much appreciated.

 

[lx200inAR]

I am sure you have done a great job as you explained.
I just found out that I have got same issue on my LX570 2011, and I am at the stage of ordering parts now.

So far I have listed these few.

Part Description	Part NO.
Manifold Gasket	17171-0S030
PCV valve	12204-380100
Water Inlet Engine Cover Pipe Gasket (O-Ring)	96761-35035
Seal Packing (Tube)	1282B

Should I add any other part to the list? Do I MUST need to change the VP Cover plate or I can used the old one if not damaged?
Also if you can suggest the sources to procure these as you mentioned it cost you way cheaper than what I am looking at online.

Much appreciated.

View attachment 3863869

You need 2 each of the O Ring and the Manifold gaskets. You shouldn't need to replace the cover.

If you decide to disconnect the SAIS pumps at the pipe to exhaust manifold interface you will need new gaskets(17377-38010 x2). Assuming you still have your SAIS system. There's also a grommet that you will expose that could stand to be replaced (12273-38020). Picture below taken from this thread.

Might try Partsouq or one of the Japanese distributors for better pricing on parts where available. Most of the parts for this job are pretty small, so shipping isn't too bad. Serra Toyota of Decatur is one of the cheaper US dealers with an online parts presence.

 

[muzzam]

You need 2 each of the O Ring and the Manifold gaskets. You shouldn't need to replace the cover.

If you decide to disconnect the SAIS pumps at the pipe to exhaust manifold interface you will need new gaskets(17377-38010 x2). Assuming you still have your SAIS system. There's also a grommet that you will expose that could stand to be replaced (12273-38020). Picture below taken from this thread.

Might try Partsouq or one of the Japanese distributors for better pricing on parts where available. Most of the parts for this job are pretty small, so shipping isn't too bad. Serra Toyota of Decatur is one of the cheaper US dealers with an online parts presence.

Thanks alot.
I will order these 2 as well, just to be ready in case.
I searched around and found local pick-up from Toyota Mike Celvert in Houston. So all good on parts.
Hope to do it over then weekend.
Much appreciated.

 

[lx200inAR]

Thanks alot.
I will order these 2 as well, just to be ready in case.
I searched around and found local pick-up from Toyota Mike Celvert in Houston. So all good on parts.
Hope to do it over then weekend.
Much appreciated.

Oh, you might consider ordering a 82219-60090 wiring harness. This is the harness for the 4 knock sensors. If you are going to break any clips during this job, it will most likely be on this harness. Don't technically need it, but it falls victim to broken clips and rodents pretty regularly.

I'm currently in the middle of this job and have had my intake manifold off a few times recently, so it's pretty fresh in my head. I assume there are some well written guides already posted.

 

[mfeferman]

Oh, you might consider ordering a 82219-60090 wiring harness. This is the harness for the 4 knock sensors. If you are going to break any clips during this job, it will most likely be on this harness. Don't technically need it, but it falls victim to broken clips and rodents pretty regularly.

I'm currently in the middle of this job and have had my intake manifold off a few times recently, so it's pretty fresh in my head. I assume there are some well written guides already posted.

Actually, I thought the knock sensors were no problem. The one I ended up breaking and having to re-pin was the one on the throttle body housing. New item by Mark Feferman - https://photos.app.goo.gl/u2sLy7Y65pzH691F9